Certificate error: "The host name in the certificate is invalid or does not match"

 Hi there,
I'm getting the above error when I try  to make a POST to an external page.
Googleing it I see it might have something to do with my SSL certificate. I created my own certificate and signed it myself, and I issued it to "localhost"
 This is my function:
  
Public Sub post_sample()
Dim data As String = "<?xml version='1.0' encoding='utf-8'?><element>A</element>"

Dim my_url As String = "https://url2.com"

Dim my_request As New MSXML2.ServerXMLHTTP60

Try
my_request.open("POST", my_url, False)
my_request.setRequestHeader("Content-type", " ...